import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
+import java.util.function.Consumer;
import java.util.function.UnaryOperator;
import javax.annotation.Nonnull;
import javax.annotation.concurrent.NotThreadSafe;
}
if (!current.cohort.getIdentifier().equals(txId)) {
- LOG.warn("{}: Head of queue is {}, ignoring consensus on transaction {}", logContext,
+ LOG.debug("{}: Head of pendingFinishCommits queue is {}, ignoring consensus on transaction {}", logContext,
current.cohort.getIdentifier(), txId);
return;
}
}
public Collection<ShardDataTreeCohort> getAndClearPendingTransactions() {
- Collection<ShardDataTreeCohort> ret = new ArrayList<>(pendingTransactions.size() + pendingCommits.size()
- + pendingFinishCommits.size());
+ Collection<ShardDataTreeCohort> ret = new ArrayList<>(getQueueSize());
for (CommitEntry entry: pendingFinishCommits) {
ret.add(entry.cohort);
@SuppressWarnings("checkstyle:IllegalCatch")
private void processNextPendingTransaction() {
- while (!pendingTransactions.isEmpty()) {
- final CommitEntry entry = pendingTransactions.peek();
+ processNextPending(pendingTransactions, State.CAN_COMMIT_PENDING, entry -> {
final SimpleShardDataTreeCohort cohort = entry.cohort;
final DataTreeModification modification = cohort.getDataTreeModification();
- if (cohort.isFailed()) {
- LOG.debug("{}: Removing failed transaction {}", logContext, cohort.getIdentifier());
- pendingTransactions.remove();
- continue;
- }
-
- if (cohort.getState() != State.CAN_COMMIT_PENDING) {
- break;
- }
-
LOG.debug("{}: Validating transaction {}", logContext, cohort.getIdentifier());
Exception cause;
try {
// Failure path: propagate the failure, remove the transaction from the queue and loop to the next one
pendingTransactions.poll().cohort.failedCanCommit(cause);
- }
+ });
+ }
- maybeRunOperationOnPendingTransactionsComplete();
+ private void processNextPending() {
+ processNextPendingFinishCommit();
+ processNextPendingCommit();
+ processNextPendingTransaction();
}
- private void processNextPendingCommit() {
- while (!pendingCommits.isEmpty()) {
- final CommitEntry entry = pendingCommits.peek();
+ private void processNextPending(Queue<CommitEntry> queue, State allowedState, Consumer<CommitEntry> processor) {
+ while (!queue.isEmpty()) {
+ final CommitEntry entry = queue.peek();
final SimpleShardDataTreeCohort cohort = entry.cohort;
if (cohort.isFailed()) {
LOG.debug("{}: Removing failed transaction {}", logContext, cohort.getIdentifier());
- pendingCommits.remove();
+ queue.remove();
continue;
}
- if (cohort.getState() == State.COMMIT_PENDING) {
- startCommit(cohort, cohort.getCandidate());
+ if (cohort.getState() == allowedState) {
+ processor.accept(entry);
}
break;
maybeRunOperationOnPendingTransactionsComplete();
}
- private void processNextPending() {
- processNextPendingCommit();
- processNextPendingTransaction();
+ private void processNextPendingCommit() {
+ processNextPending(pendingCommits, State.COMMIT_PENDING,
+ entry -> startCommit(entry.cohort, entry.cohort.getCandidate()));
+ }
+
+ private void processNextPendingFinishCommit() {
+ processNextPending(pendingFinishCommits, State.FINISH_COMMIT_PENDING,
+ entry -> payloadReplicationComplete(entry.cohort.getIdentifier()));
+ }
+
+ private boolean peekNextPendingCommit() {
+ final CommitEntry first = pendingCommits.peek();
+ return first != null && first.cohort.getState() == State.COMMIT_PENDING;
}
void startCanCommit(final SimpleShardDataTreeCohort cohort) {
final SimpleShardDataTreeCohort current = entry.cohort;
Verify.verify(cohort.equals(current), "Attempted to pre-commit %s while %s is pending", cohort, current);
+
+ LOG.debug("{}: Preparing transaction {}", logContext, current.getIdentifier());
+
final DataTreeCandidateTip candidate;
try {
candidate = tip.prepare(cohort.getDataTreeModification());
- } catch (Exception e) {
- failPreCommit(e);
- return;
- }
-
- try {
cohort.userPreCommit(candidate);
- } catch (ExecutionException | TimeoutException e) {
+ } catch (ExecutionException | TimeoutException | RuntimeException e) {
failPreCommit(e);
return;
}
pendingTransactions.remove();
pendingCommits.add(entry);
+
+ LOG.debug("{}: Transaction {} prepared", logContext, current.getIdentifier());
+
cohort.successfulPreCommit(candidate);
processNextPendingTransaction();
return;
}
+ LOG.debug("{}: Starting commit for transaction {}", logContext, current.getIdentifier());
+
+ final TransactionIdentifier txId = cohort.getIdentifier();
if (shard.canSkipPayload() || candidate.getRootNode().getModificationType() == ModificationType.UNMODIFIED) {
LOG.debug("{}: No replication required, proceeding to finish commit", logContext);
pendingCommits.remove();
pendingFinishCommits.add(entry);
- finishCommit(cohort);
+ cohort.finishCommitPending();
+ payloadReplicationComplete(txId);
return;
}
- final TransactionIdentifier txId = cohort.getIdentifier();
final Payload payload;
try {
payload = CommitTransactionPayload.create(txId, candidate);
-
- // Once completed, we will continue via payloadReplicationComplete
- entry.lastAccess = shard.ticker().read();
- shard.persistPayload(txId, payload);
-
- LOG.debug("{}: Transaction {} submitted to persistence", logContext, txId);
-
- pendingCommits.remove();
- pendingFinishCommits.add(entry);
} catch (IOException e) {
LOG.error("{}: Failed to encode transaction {} candidate {}", logContext, txId, candidate, e);
pendingCommits.poll().cohort.failedCommit(e);
+ processNextPending();
return;
}
- processNextPending();
+ // We process next transactions pending canCommit before we call persistPayload to possibly progress subsequent
+ // transactions to the COMMIT_PENDING state so the payloads can be batched for replication. This is done for
+ // single-shard transactions that immediately transition from canCommit to preCommit to commit. Note that
+ // if the next pending transaction is progressed to COMMIT_PENDING and this method (startCommit) is called,
+ // the next transaction will not attempt to replicate b/c the current transaction is still at the head of the
+ // pendingCommits queue.
+ processNextPendingTransaction();
+
+ // After processing next pending transactions, we can now remove the current transaction from pendingCommits.
+ // Note this must be done before the call to peekNextPendingCommit below so we check the next transaction
+ // in order to properly determine the batchHint flag for the call to persistPayload.
+ pendingCommits.remove();
+ pendingFinishCommits.add(entry);
+
+ // See if the next transaction is pending commit (ie in the COMMIT_PENDING state) so it can be batched with
+ // this transaction for replication.
+ boolean replicationBatchHint = peekNextPendingCommit();
+
+ // Once completed, we will continue via payloadReplicationComplete
+ shard.persistPayload(txId, payload, replicationBatchHint);
+
+ entry.lastAccess = shard.ticker().read();
+
+ LOG.debug("{}: Transaction {} submitted to persistence", logContext, txId);
+
+ // Process the next transaction pending commit, if any. If there is one it will be batched with this
+ // transaction for replication.
+ processNextPendingCommit();
}
void processCohortRegistryCommand(final ActorRef sender, final CohortRegistryCommand message) {
return true;
} else {
- newTip = MoreObjects.firstNonNull(e.cohort.getCandidate(), dataTree);
+ newTip = MoreObjects.firstNonNull(e.cohort.getCandidate(), newTip);
}
}
Code Review / controller.git / blobdiff